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Thermoluminescence properties of undoped diamond films deposited using HF CVD technique

Paprocki K., Winiecki J., Kabacińska R., Przegiętka K., Szybowicz M., Fabisiak K.

Materials Science Poland

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2017

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Vol. 35, No. 4

785--790

EN

Natural diamond has been considered as a perspective material for clinical radiation dosimetry due to its tissue biocompatibility and chemical inertness. However, the use of natural diamond in radiation dosimetry has been halted by the high market price. The recent progress in the development of CVD techniques for diamond synthesis, offering the capability of growing high quality diamond layers, has renewed the interest in using this material in radiation dosimeters having small geometrical sizes. Polycrystalline CVD diamond films have been proposed as detectors and dosimeters of β and α radiation with prospective applications in high-energy photon dosimetry. In this work, we present a study on the TL properties of undoped diamond film samples grown by the hot filament CVD (HF CVD) method and exposed to β and α radiation. The glow curves for both types of radiation show similar character and can be decomposed into three components. The dominant TL peaks are centered at around 610 K and exhibit activation energy of the order of 0.90 eV.

2

Electrical properties and Mott parameters of polycrystalline diamond films synthesized by HF CVD method from hydrogen/methanol gas mixture

Banaszak-Piechowska A., Fabisiak K., Staryga E., Paprocki K.

Materials Science Poland

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2017

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Vol. 35, No. 4

830--837

EN

The influence of diamond crystallinity and preferred orientation on electronic conductivity of synthetic diamond films grown by hot filament chemical vapour deposition (HFCVD) was investigated. The CVD diamond films of different morphologies and crystallite sizes varying from 36 nm to 67 nm, measured in ‹2 2 0› direction were considered. The charge transport mechanism in the diamond samples was studied using temperature dependent DC conductivity measurements. The obtained results showed that in the temperature range of 90 K to 300 K charge transport is realized via Variable Range Hopping (VRH, m = 1/4) mechanism. Using VRH model, the Mott parameters were evaluated i.e. density of states at Fermi level N(EF) (0.22 × 1015 eV-1·cm-3 to 1.7 × 1015 eV-1·cm-3), hopping energy W (43.5 meV to 142.3 meV) and average hopping distance R (1.49 × 10-5cm to 2.56 × 10-5cm). It was shown that above mentioned parameters strongly depend on diamond film preferential orientation.

3

Chemically vapor deposited diamond films as dosimetric material for potential clinical applications

Kabacińska R., Winiecki J., Przegiętka K., Szybowicz M., Fabisiak K., Paprocki K.

Materials Science Poland

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2017

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Vol. 35, No. 4

702--706

EN

Thermally stimulated luminescence (TL), cathodoluminescence (CL) and Raman spectroscopy of CVD diamond films grown on silicon substrates have been studied in order to obtain information on defects created during the growth, which induce the levels within the gap. TL between 300 K and 700 K, and CL from 200 nm to 1200 nm have been teasured. The glow curves show a peak located around 610 K with different intensities, depending on the sample thickness, associated with a trap of energy, equal to 0.83 eV and with attempt-to-escape-time of the order of 108 s-1. Broad CL bands observed at 428±1 nm (2.90 ±0.01 eV) and 500±1 nm (2.47±0.004 eV) are attributed to closely spaced and widely separated donor-acceptor (D-A) pairs, respectively. The TL and CL results were correlated with diamond quality estimated from Raman spectroscopy measurements.

4

Effect of annealing temperature on optical and electrical properties of metallophthalocyanine thin films deposited on silicon substrate

Skonieczny R., Popielarski P., Bała W., Fabisiak K., Paprocki K., Jancelewicz M., Kowalska M., Szybowicz M.

Materials Science Poland

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2016

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Vol. 34, No. 3

676--683

EN

The cobalt phthalocyanine (CoPc) thin films (300 nm thick) deposited on n-type silicon substrate have been studied using micro-Raman spectroscopy, atomic force spectroscopy (AFM) and I-V measurement. The CoPc thin layers have been deposited at room temperature by the quasi-molecular beam evaporation technique. The micro-Raman spectra of CoPc thin films have been recorded in the spectral range of 1000 cm-1 to 1900 cm-1 using 488 nm excitation wavelength. Moreover, using surface Raman mapping it was possible to obtain information about polymorphic forms distribution (before and after annealing) of metallophthalocyanine (α and β form) from polarized Raman spectra. The I-V characteristics of the Au/CoPc/n-Si/Al Schottky barrier were also investigated. The obtained results showed that influence of the annealing process plays a crucial role in the ordering and electrical conductivity of the molecular structure of CoPc thin films deposited on n-type silicon substrate.

5

Badanie jakościowe materiałów węglowych za pomocą spektroskopii Ramana

Dychalska A., Paprocki K., Fabisiak K., Szybowicz M.

LAB Laboratoria, Aparatura, Badania

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2016

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R. 21, nr 5

6--7

PL

Praca ta prezentuje możliwość zastosowania spektroskopii Ramana do badań jakościowych materiałów węglowych typu DLC (diamond-like carbon). Badania zmiany parametrów spektralnych pasm charakterystycznych D i G w zakresie od temperatury pokojowej do 300°C umożliwiły obserwację wpływu procesu wygrzewania na przechodzenie materiału z formy węgla amorficznego do formy zbliżonej do nanokrystalicznego grafitu.

6

Temperature dependence of stress in CVD diamond films studied by Raman spectroscopy

Dychalska A., Fabisiak K., Paprocki K., Dudkowiak A., Szybowicz M.

Materials Science Poland

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2015

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Vol. 33, No. 3

620--626

EN

Evolution of residual stress and its components with increasing temperature in chemical vapor deposited (CVD) diamond films has a crucial impact on their high temperature applications. In this work we investigated temperature dependence of stress in CVD diamond film deposited on Si(100) substrate in the temperature range of 30 degrees C to 480 degrees C by Raman mapping measurement. Raman shift of the characteristic diamond band peaked at 1332 cm(-1) was studied to evaluate the residual stress distribution at the diamond surface. A new approach was applied to calculate thermal stress evolution with increasing temperature by using two commonly known equations. Comparison of the results obtained from the two methods was presented. The intrinsic stress component was calculated from the difference between average values of residual and thermal stress and then its temperature dependence was discussed.

7

Study of CVD diamond layers with amorphous carbon admixture by Raman scattering spectroscopy

Dychalska A., Popielarski P., Franków W., Fabisiak K., Paprocki K., Szybowicz M.

Materials Science Poland

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2015

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Vol. 33, No. 4

799--805

EN

Raman spectroscopy is a most often used standard technique for characterization of different carbon materials. In this work we present the Raman spectra of polycrystalline diamond layers of different quality, synthesized by Hot Filament Chemical Vapor Deposition method (HF CVD). We show how to use Raman spectroscopy for the analysis of the Raman bands to determine the structure of diamond films as well as the structure of amorphous carbon admixture. Raman spectroscopy has become an important technique for the analysis of CVD diamond films. The first-order diamond Raman peak at ca. 1332 cm−1 is an unambiguous evidence for the presence of diamond phase in the deposited layer. However, the existence of non-diamond carbon components in a CVD diamond layer produces several overlapping peaks in the same wavenumber region as the first order diamond peak. The intensities, wavenumber, full width at half maximum (FWHM) of these bands are dependent on quality of diamond layer which is dependent on the deposition conditions. The aim of the present work is to relate the features of diamond Raman spectra to the features of Raman spectra of non-diamond phase admixture and occurrence of other carbon structures in the obtained diamond thin films.

8

CVD diamond layers for electrochemistry

Kowalska M., Fabisiak K., Wrzyszczyński A., Banaszak A., Szybowicz M., Paprocki K., Bała W, Bylicki F

Materials Science Poland

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2014

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Vol. 32, No. 3

475--480

EN

Diamond electrodes of different morphologies and qualities were manufactured by hot filament chemical deposition (HF CVD) techniques by changing the parameters of diamond growth process. The estimation of diamond quality and identification of different carbon phases was performed by Raman spectroscopy measurements. The effect of diamond quality and amorphous carbon phase content on the electrochemical response of an obtained diamond electrode in 0.5 M H2SO4 as supporting electrolyte was investigated by cyclic voltammetry with [Fe(CN)6]4−/3− as a redox probe. The kinetic parameters such as catalytic reaction rate constant k0 and electron transfer coefficient α were determined. The obtained results show that the analytical performance of undoped diamond electrodes can be implemented just by the change of diamond layers quality.

9

Diament jako materiał przetwornikowy do produkcji biosensorów

Mosińska L., Fabisiak K., Paprocki K., Kowalska M., Popielarski P., Szybowicz M., Stasiak A.

Przemysł Chemiczny

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2013

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T. 92, nr 6

919--923

10

Cyclic voltammetry and impedance studies of undoped diamond films

Mosińska L., Kowalska M., Popielarski P., Fabisiak K., Paprocki K., Szybowicz M., Wrzyszczynski A., Zhusupkalieva G. K.

Materials Science Poland

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2013

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Vol. 31, No. 1

146-150

EN

The undoped, polycrystalline diamond films were deposited on tungsten wire substrates by hot filament chemical vapor deposition (HF CVD), using a precursor gas mixture of methanol with excess of hydrogen. The morphology and quality of the as-deposited films were monitored by scanning electron microscopy (SEM) and Raman spectroscopy. The surface morphology analyzed by SEM resembles a continuous and well faceted diamond film. Raman results showed essential differences in qualities of diamond films grown at different hydrocarbon concentrations. The electrochemical properties of diamond electrodes were examined with cyclic voltammetry (CV) and the electrochemical impedance spectroscopy (EIS). The CV experiments revealed a large chemical window (>~4.3 V) of undoped diamond. Analysis of the ferrocyanide-ferricyanide couple at a diamond electrode suggests some extent of electrochemical quasi-reversibility, but the rates of charge transfer across the diamond substrate interface vary with diamond quality.

11

The application of CVD diamond films in cyclic voltammetry

Torz-Piotrowska R., Wrzyszczyński A., Paprocki K., Screiber M., Uniszkiewicz C., Staryga E.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

486-491

EN

Purpose: The main purpose of these studies was to show the applicability of CVD (Chemical Vapour Deposition) diamond layer in electrochemistry and to work out the technology of manufacturing diamond electrodes. Design/methodology/approach: The diamond films were deposited on tungsten substrate by HF CVD technique, and then, their quality was checked by Raman spectroscopy. It was shown, using Cyclic Voltammetry (CV) measurements, that un-doped diamond films are chemically stable in aqueous solutions. Findings: The results of cyclic voltammetry measurements show that diamond electrode on tungsten substrate is electrochemically stable in aqueous solutions over a wide potential range (-3000 mV to 2000 mV). The Raman spectra confirmed the good quality of obtained diamond layer. Research limitations/implications: In particular, it was shown that diamond electrode showed a wide potential window, very low background current, chemical and physical stability. Practical implications: Presented results showed that CVD diamond films can find application in production of diamond electrodes for electrochemical application. The sensitivity of CVD diamond layers to the electroactive species indicates on possibility of application of this material for construction of chemical and biological sensors. Originality/value: The characteristics of diamond electrodes and the resistivity of this material to the chemical attack indicate that it can be employed in a number of electrochemical applications and additionally it can work in harsh environment. The HF CVD diamond layer seems to be the new, promising and versatile material for electrochemical applications.

12

Forming the High quality CoSi2 by solid phase epitaxy

Mazurek P., Daniluk A., Paprocki K.

Optica Applicata

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2002

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Vol. 32, nr 3

389-395

EN

Thin film of CoSi2 were grown on Si(111) by solid phase epitaxy (template technique) in UHV condition. We present a practical experimental procedure for the preparation of thin epitaxial films of cobalt silicide. Layers obtained by the deposition of metal on silicon (111) demonstrate a high-quality crystallographic structure. The state of the surface of growing layers is studied with the in situ combination of reflection high=energy electron diffraction (RHEED) azimuthal plots and rocking curve.

13

Initial growth stage of CaF₂ on Si(111) studied by rheed

Daniluk A., Mazurek P., Paprocki K., Mikołajczak P.

Electron Technology

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1998

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Vol. 31, No. 3/4

338-341

EN

Analyses of reflection high-energy electron diffraction (RHEED) intensity changes observed during initial stages of heteroepitaxial growth of calcium fluoride (CaF₂) on Si(111) substrate were presented. Layers obtained by deposition of CaF₂ on a hot (550°C) substrate demonstrate a high-quality crystallographic structure. The state of the surfaces of growing layers is being researched with the in situ of RHEED rocking curve.

14

Apparatus for the measurement of critical temperature in metallic quantum wells

Orłowski M., Paprocki K., Korczak Z., Jałochowski M.

Electron Technology

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1998

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Vol. 31, No. 3/4

516-519

EN

The apper describes construction of UHV apparatus and the method of critical temperature measurement of thin Pb layers. Electronic setup for specific resistivity measurement Pb layers during thier deposition on Si(111) substrate is presented. The results obtained during specific resistivity measurements of Pb layers at temperatures above Tc illustrates the accuracy of proposed measuremement method.